1. Field of the Invention
Embodiments relate to a battery pack.
2. Description of the Related Art
In recent years, there have been actively developed and produced compact and light portable electric/electronic devices such as cellular phones, notebook computers, camcorders, etc. Therefore, the portable electric/electronic devices are equipped with built-in battery packs, such that these devices can be operated even in places where additional power sources are not furnished. The battery packs recently employ chargeable/dischargeable secondary batteries in terms of economic interests. Typical examples of the secondary batteries may include a nickel-cadmium (Ni—Cd) battery, a nickel-metal hydride (Ni-MH) battery, a lithium (Li) battery and a lithium ion (Li-ion) secondary battery. In particular, the lithium ion secondary battery has a high drive voltage which is three times higher than that of the Ni—Cd or Ni-MH battery that is widely used as a power source for portable electronic devices. Further, the lithium ion secondary battery has a high energy density per unit weight.
Generally, the secondary batteries use a lithium oxide as a positive electrode active material and a carbonaceous material as a negative electrode active material, respectively. Lithium secondary batteries are classified into two groups, i.e. liquid electrolyte batteries and polymer electrolyte batteries, depending on the kinds of electrolytes. The batteries using liquid electrolytes are referred to as lithium ion batteries, whereas the batteries using polymer electrolytes are referred to as lithium polymer batteries.
The secondary battery is formed by electrical connection of a bare cell including an electrode assembly and an electrolyte in a case with a protection circuit board. The bare cell performs charge and discharge of electricity via chemical reactions, and the protection circuit board prevents overcharge and overdischarge of the bare cell to thereby protect the bare cell. An assembled state of the bare cell and the protection circuit board is referred to as a core-pack. The protection circuit board of the core pack is provided with a connector. The connector transmits an electric current generated from the bare cell to an external device during discharge of the battery, and serves as a current-charging path during charging of the battery.
In addition, the core pack is resin-molded or is provided with the attachment of an insulating frame, in order to electrically insulate the bare cell from the protection circuit board and protect the bare cell against external impact.
The resin molding of the core pack has a disadvantage of poor moldability. For this reason, assembling of the insulating frame into the core pack is popular. However, the insulating frame is vulnerable to external impact.
As a consequence, upon connection of the core pack to the insulating frame, the connector may be separated from the protection circuit board due to external impact. Further, application of external impact may result in separation of the insulating frame from the core pack.